Blades for earth moving machines

ABSTRACT

A cutting-edge member for scraper blades having interlocking engagement with adjacent members, each cutting edge member being adjustable and reversible in a position relative to the other members. The interlocking engagement is achieved by the use of non-tapered, angled dove-tailed members spaced along each side of the cutting edge member and being separated by recesses, each dove-tailed member being of a size and shape the same as each of the recesses.

This invention relates to improvements in blades for earth movingmachines such as scrapers, graders, bulldozers and so on (hereinafterreferred to as "scrapers") and it refers particularly to the cuttingedges- the operative cutting edge portions of the blades.

The ground-engaging tools of bulldozers, scrapers, graders and otherearth moving machines are made in a wide variety of types, according tothe purposes for which the tools are to be used. In general, there arereplaceable edge members capable of being bolted in position on asupport assembly, such as a scraper moldboard, and those edge membersmay be made to suit a level cut arrangement (with the front edges of theseveral members all in line), in a drop centre or stinger arrangement(when the middle part projects forwardly of the two or more side parts),with integral forwardly-projecting teeth, with replaceable forwardlyprojecting teeth, substantially planar in shape, or, if necessary,curved, with front and rear edges so that they may be reversed, and soon. The edge members for a machine may be made in one piece to extendthe full width of the tools to which they are to be attached or they maybe made in shorter sections so that three four or more members arebolted in position on a support member to make up the full width of theearth-engaging tool.

In my earlier U.S. Pat. No. 4,457,380 there is described and defined ablade for scrapers. However, that blade has been found to have certainlimitations. If it is desired to remove a female blade to either rotateit or replace due to wear, or for any other reason, both that blade andthe adjacent two male blades, must be removed. Also, it is difficult torotate just the one female blade due to every second blade beingdifferent.

This invention is applicable to all such edge members but for simplicityof description they will be referred to as cutting edges or edge membersfor scraper blades without limiting the invention to the blades of suchmachines.

This invention has been devised particularly with the object ofproviding a construction of cutting edge for a scraper blade such thatthe range of use of the cutting edge will be greatly increased. Anotherobject is to provide cutting edges so constructed that they may beindividually reversed in position, interchanged, and/or used in thestraight or level-cut operational position or in the so-called "drop" or"stinger" position, as required. A further object is to provide cuttingedges which, individually, will be easy to replace and/or adjust inposition.

Yet another object is to provide a cutting edge of such constructionsthat a broken or worn part of the cutting edge may be replaced withoutthe necessity of replacing the whole cutting edge.

The invention devised with these and other objects in view providescutting edge members for scraper blades having means for interlockingwith adjacent cutting edges whereby each cutting edge, when securelymounted in position on a scraper moldboard, will be engaged with theadjacent cutting edge or edges, the cutting edge members beingadjustable and reversible in position one relative to the other.

It is preferred that the means for interlocking be angle dovetailedparts on the opposite side edges of the cutting edge members so arrangedthat when two such cutting edge members are mounted on a scrapermoldboard in side-by-side relationship the angled dovetailed parts onone side of one such cutting edge member will interengage with those onthe adjacent side of the next cutting edge member. It is also preferredthat each of the cutting edge members be provided with at least twofastening holes by which it may be fastened to the scraper blade, andthat the dovetailed parts have a spacing or pitch related to thelocation and spacing of said holes so that if a cutting edge member ismoved, relative to an adjacent cutting edge member, the dovetailed partswill still interengage so as to lock together the two said cutting edgemembers.

The angled dovetailed parts on one cutting edge member are not tapered,so that they are the same width at the top as at the bottom, therecesses between said dovetail parts being the same shape as thedovetail parts of the first-mentioned cutting edge member. Thus, thecutting edge members will be adapted to interlock in the longitudinaldirection and transverse directions, and in the vertical direction aswell-considering the cutting edge members as being horizontal.

In order to provide for a reversal of each cutting edge member so that,when one end is worn, it may be turned end-for-end and an unworn end putinto operational position, each end is shaped to provide a desired"edge" and the dovetailed parts of the two different cutting edgemembers will be arranged so that they will interengage even when one ofthem is reversed in position relative to the other without any change inrelated position of the fastening holes.

With the present invention, the two cutting edges are substantiallyparallel so that rotation about the horizontal transverse axis of thecutting edge member is required to effect reversal.

Also, the spacing or pitch of the angled dovetailed parts in relation tothe spacing of the fastening holes is such that one cutting edge membermay be moved longitudinally relative to the adjacent members into a dropcenter or stinger position, and be bolted in that position.

In order that the invention may be readily understood and convenientlyput into practical form I shall now describe with reference to theaccompanying illustrative drawings one exemplary construction of cuttingedges for moving machines:

FIG. 1 is a plan view of a pair of members in interengaged relationship.

FIG. 2 is a side view in the direction of arrow 2 of FIG. 1;

FIG. 3 is a side view in the direction of arrow 3 of FIG. 1;

FIG. 4 is a transverse cross-section on the line and in the direction ofarrows 4--4 of FIG. 1;

FIG. 5 is a perspective view of the two members of FIG. 1 prior to theirinterengagement;

FIG. 6 shows a plan view of the members in adjusted relative positions;

FIG. 7 is a side view of the members prior to interengagement;

FIG. 8 is a plan view of a pair of members of a second embodiment ininterengaged relationship;

FIG. 9 is a side view in the direction of arrow 9 of FIG. 8; and

FIG. 10 is a perspective view of the two members of FIG. 8 prior totheir interengagement.

According to this invention the cutting edge of a scraper (or otherearth moving machine as defined above) is made up of a number of membersA and members B which are arranged in side-by-side interengagingrelationship. In these drawings only one of each member is illustratedbut it will be appreciated that there are provided as many as may berequired to extend the full width of the scraper blade.

Each of the members A and B has a body portion 11 with a flat underside12, a flat upper side 13, substantially parallel front and rear ends 14and 15 respectively each forming an edge, and opposite side walls madefor interlocking engagement with the side walls of adjacent members. Ineach body portion 11 are two longitudinally spaced fastening holes 16made to receive the fastening bolts by which the cutting edge membersare fastened to the scraper moldboard. The effective width of each ofthe cutting edge members is such that when they are fastened togetherthe fastening holes 16 will be spaced laterally a distance to suit thespacing of the fastening holes in the scraper moldboard

The two side walls 17, 18 of each member A are provided with a series ofundercut, angled dovetail recesses 19, which are of constant width fromtop to bottom, and end pieces 20 at the opposite ends. The side walls21, 20 of each member B have a series of dovetail parts 23 of a shape,size and longitudinal spacing corresponding to the dimensions of thedovetail recesses 19 so as to be capable of being fitted thereinto.

The spacing of the dovetail recesses 19 is the same on the two sides ofeach member A and, similarly, the spacing of the male dovetail parts 23is the same on each side of each member B. The dovetail recesses 19 andlands 24 between them are so arranged that on each side of each memberA, a land 24 is in transverse alignment with a fastening hole 16, thepitch of the dovetail recesses 19 and of the dovetail parts 23 being thesame as the longitudinal spacing of the fastening holes 16. The dovetailparts 23 are similarly spaced as the dovetail recesses 19 and extendsalong both sides of each member B. The dovetail parts 23 are separatedby a series of undercut angled dovetail recesses 25, the spacing orpitch of the recesses 25 related to the spacing of the fastening holes16.

The relationship between the spacing or pitch of the recesses 25 andspacing of the fastening holes 16 is such that the transversecentre-line of a hole 16 must pass through the point generallydesignated as C on FIG. 3, the point C being the intersection of the twodiagonal lines of the recess 25.

Most preferably, and as illustrated, the recesses 19 and 25 areidentical, as are the parts 23 and lands 24. In this way, the onlydifference between the members A and B is the location of the recesses19,25 along their lengths, this being necessary for the interfitting ofmembers A & B.

It is clear that with that arrangement and spacing of the dovetailrecesses 19 and dovetail parts 23, when a number of members areconnected together in interlocking arrangement, a member may be removedfrom the scraper mole blade to which it is fastened, reversedend-for-end about the horizontal transverse axis and re-engaged with theadjacent member or members.

Further, if it is desired to set a number of the cutting edge members inthe drop position those members may be moved longitudinally forwards inrelation to the remaining members, in the manner as illustrated in FIG.6, by the amount of one or more pitches of the dovetail parts 23 andthen re-bolted in position.

It is believed that when a number of cutting edge members made accordingto the invention are correctly bolted to a scraper moldboard and thescraper is being so operated that the cutting edges dig into the groundthe pressure on the several edge members is in an anti-clockwisedirection and the individual edge members will lock with the adjacentmembers by virtue of the undercut nature of the recesses 19,25 andcorresponding shape of the parts 23,24; similarly, when the machine isoperated to move forwardly the pressure on the edge members is in theopposite direction, and the individual edge members will again lock withadjacent members of the interengaging dovetail parts.

FIGS. 8 to 10 illustrate an alternative embodiment. Here, the twomembers, now both marked C, are identical. The left member, indicated bythe addition of the suffix letter L, has on its right side a series ofundercut, angled, dovetailed recesses 219, the recesses being identicalto the recesses 19. Between the recesses 219 are lands 224, identical tothe lands 24. At each end would be end pieces 220. On its left side, themember CL has again a series of undercut, angled, dovetailed recesses219 and lands 224. The left side has its lands 224 aligned transverselywith the recesses 219 of the right side. The right of the two members,indicated by the addition of the suffix letter R, has the same recesses219 and lands 224 and the member CL, and is identical to the member CL.In this way, a plurality of identical members C can be laid side-by-sidein correct alignment. Naturally, an end member (not shown) may be addedat each or either end of the installation, if desired.

As the cutting edge members are made relatively narrow in the transversedirection each cutting edge members will be substantially lighter thancutting edges as hitherto provided and one man will be able to handlethem with ease, so that one operator may replace or change the positionof a cutting edge member, or a number of cutting edge members, on hisown.

It will be understood that the cutting edge members as herein describedmay be made as toothed cutting edge members-each said cutting edgemember having one or more teeth at one or both ends-or they may be madeto support replaceable teeth in known manner.

It is to be appreciated that other modifications in details of design,construction and/or arrangement may be made and that the invention isnot limited to the particular constructions of cutting edges describedabove in detail. All such modifications are to be deemed to be includedin the ambit of the invention as described.

I claim:
 1. A cutting-edge member for scraper blades having means forinterlocking engagement with adjacent like cutting-edge members, eachcutting edge member being adjustable and reversible in position relativeto said adjacent like cutting-edge members, said means for interlockingcomprising non-tapered angled dovetailed members spaced along each sideof each cutting-edge member and being separated by recesses, eachdovetailed member being of a size and shape the same as each of saidrecesses.
 2. A cutting-edge member as claimed in claim 1, wherein eachdovetailed member has parallel side walls which are undercut and arealso inclined to the vertical.
 3. A cutting-edge member as claimed inclaim 1, wherein there is provided at least two fastening holes by whichsaid cutting-edge member may be fastened to said scraper blade.
 4. Acutting-edge member as claimed in claim 2, wherein said dovetailedmembers have a spacing related to the location and spacing of saidfastening holes.
 5. A cutting-edge member as claimed in claim 1 whereineach end has an edge, said edges being substantially parallel.
 6. Acutting-edge member as claimed in claim 1 wherein said dovetailedmembers along one side of cutting-edge members are transversely alignedwith said recesses along the other side of said cutting-edge member. 7.A cutting-edge member as claimed in claim 1, wherein said reversibilityis by removing the cutting-edge member and pivoting about the horizontaltransverse axis of said cutting edge member.